When it comes to the timing of autumn color in different North American locations, the major factor is dwindling daylight, said Mike Pigott, senior meteorologist with AccuWeather in State College, Pennsylvania.

"It's mainly a product of shorter days and longer nights that begin to shut down photosynthesis," Pigott said. "At the northern latitudes you have noticeably shorter days in the fall versus the South. So that's the primary reason why, as a rule of thumb, the further south you are the later the leaves will change color."

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This pattern creates a colorful wave that begins in the North and rolls like a tide southward through North America—though temperature differences at higher elevations mean some southern mountains keep schedules that are more like their northern neighbors'.

Historical data suggest an early November foliage peak across a belt of the southeastern U.S., stretching from Arkansas through Georgia to the western Carolinas. Mitch Cohen, interpretative manager at Georgia's Chattahoochee-Oconee National Forest, said that's holding true this year, and there's still good fall color at the southern end of the Appalachian mountain chain.

"The color at higher elevations has peaked, but we've been having very good color at the mid-elevations," Cohen said. "This week the lower elevations here on the southern edge of the mountains are really going to be at peak."

Farther west, Arkansas leaf peepers are currently reporting a banner year for vibrant oaks, hickories, and other species across much of the state. Arkansas's official foliage update shows plenty of areas approaching peak colors this week.

The Ozark National Forest in northern Arkansas is at near-peak conditions, while Hot Springs and other central Arkansas spots are still building toward their best color, which is expected soon. In southeastern Arkansas, the season will linger a bit longer, as understory species like sumac and dogwood are turning bright golden colors and are expected peak around the weekend of November 11-13.

Forest spokesperson Joanie Bosworth said the colors are arriving just in time to welcome peepers.

"The needles of our western larch or tamarack are turning a bright golden hue, while the huckleberries and ninebarks are creating these clumps of red and orange across the forest." The riverbeds and drainages are also filled with colorful cottonwoods, she added.

In the Midwest volunteer leaf-peepers on the Foliage Network suggest there's still last-minute foliage to be seen in western Ohio, southern Michigan, and along the Wisconsin shoreline of Lake Michigan.

Video: Autumn Leaf Hoppers

The mid-Atlantic traditionally boasts some late-peaking places too—but Mother Nature threw many of them a curveball last week. Some parts of southeastern Pennsylvania, southern New Jersey, and Delaware are nearing peak foliage conditions. But while color abounds in some spots, others were wiped clean by last weekend's Halloween snowstorm.

Virginiareports plenty of color, even in the mountainous Shenandoah Valley. There, most of the summits are now past peak, but the scenic valley floors are still draped in their fall hues. The state's Piedmont region will peak soon, and colors won't be at their best in the coastal-plain region until the middle of the month.